Aircraft carrier deck coating nasl-c-1230

ABSTRACT

A HIGH PERFORMANCE NON-SLIP DECK COATING FOR DECK AREAS OF SHIPS THAT LONG POT-LIFE, CURES READILY OVER A WIDE TEMPERATURE RANGE INCLUDING BELOW 50 DEGREE TEMPERATURES AND WHEN APPLIED IS THICKER, TOUGHER, AND MORE RESISTANT TO WEAR AND SHOCK THAN CURRENTLY USED NONSLIP DECK COATINGS.

States Patent Oflice US. Cl. 260--31.2 2 Claims ABSTRACT OF THE DISCLOSURE A high performance non-slipdeck coating for deck areas of ships that has long pot-life, cures readily over a wide temperature range including below 50 degree temperatures and when applied is' thicker, tougher, and

more resistant to wear and shock than currently used nonslip deck coatings.

BACKGROUND OF THE INVENTION Lightweight non-slip deck coatings have been in use on U.S. Navy 'aircraft'carrier flight and hangar decks to provide traction for maneuvering aircraft and various wheeledive'hicles andlto provide secure footing for planehandling personnel under the particular combination of hazardous conditions that is normal aboard an aircraft carrier. Sea spray, rain, petroleum product spillages, and the complex motions of the ship added to fiurries of heavy trafliccombine to present unique dangers. A mixture including a two-part epoxy matrix has been used but has the disadvantages of short pot-life after mixing of materials, does not cure satisfactorily below 50 degrees, and has required frequent patch repair in service because of poor adhesion to wood andmetal surfaces in the nautical environment. There has been a need for coating material with longer pot-life, lower minimum cure temperature, improved adhesion, and better wear resistance.

SUMMARY OF THE INVENTION The general purpose of this invention is to provide a non-slip deck coating that has all the advantages of similarly employed prior art coatings and has none of the above described disadvantages. To attain this, the present invention provides a unique composition of ingredients divided into two groups. The dry group and liquid groups are stored separately and mixed just prior to application of the coating to the surface.

An object of the present invention is to provide a high performance deck coating suitable to provide non-slip traction which is reliable, inexpensive and easily applied.

Another object is to provide a non-slip deck coating mixture which may be stored in separate containers and has a relatively long pot or shelf life.

Still another object is to provide a non-slip deck coating which may be readily cured over an extremely large temperature range and which may be readily cured over an extremely large temperature range and which is tough and highly wear resistant.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description.

DESCRIPTION OF A PREFERRED EMBODIMENT The coating ingredients are stored as a two-part package proportioned as above. One part contains all the liquid ingredients, namely the polyurethane prepolymer, amyl acetate and anhydrous xylene blended together, while the other part contains the dry ingredients, namely the natural 3,652,485 Patented Mar. 28, 1972 emery grit, asbestos floats, magnesium silicate and carbon black blended together. The xylene and amyl acetate must be of a grade that is essentially free of water, else some polymerization in the resin will occur during storage. Storage as a two-part package obviates the excess cost incurred by subjecting all the dry ingredients to a dehydration process. To ready for application; the contents of a dry ingredient package are slowly stirred into the contents of the liquid ingredient package in a mechanical mixer. The combined ingredients are mixed until the dry ingredients are thoroughly wetted. The mixture has a useful pot-life of up to 24 hours. It has proven to be efficient 'to package dry and liquid ingredients in suflicient quantity for approximately five gallons mixed since up to that amount can be readily applied even on a deck that is as hot as 140 F. and when spread covers an area of approximately 150 square feet, an area that is reasonable for one man to work after the entire mixture is deposited on the deck. The mixture is poured out of its container onto the deck. It flows readily and spreads rapidly to form a very shallow puddle. The puddle is spread to the desired coating thickness with a masonry trowel or with a longhandled paint roller to the desired coating thickness. When applied in the above manner, the emery particles are closely spaced and generally one particle deep and the binder matrix between the particles has a thickness which is a minor fraction of the emery particle dimensions. The binder matrix has demonstrated the properties of excellent adhesion, toughness, impact resistance, flexibility, durability, good particle retentivity and long wear resistance. The coating applies easily over the range of temperatures experienced by an aircraft carrier flight deck and an aircraft carrier hangar deck. We discovered that the coating adheres exceptionally well to any moderately clean substrate to which it is applied. The coating was ap plied onto wood, steel, stainless steel, aluminum, and over oil paint and old deck coating and where the surfaces were dry, wet and even submerged. In all instances the coatings set and adhered well.

An example of one suitable and satisfactory coating mixture is as follows:

Parts by wt. Polyurethane resin (moisture curing) 48 Amyl acetate 6 Xylene (anhydrous) 6 Magnesium silicate (325 mesh) 20 Asbestos floats (fine fibers) l0 Emery grit 12/30 sieve size 115 The moisture-curing polyurethane resin is prepared by reacting under reflux conditions and under an inert atmosphere; a drol or triol or any other polyhydroxy compound (polyether polyols, polyester polyols or castor oil) with toluene di-isocyanate in a solvent system, the ratio of the isocyanate to the polyhydroxy being 2.1/1. The reaction temperature is maintained at reflux and the rate of reaction is controlled by checking the free NCO of the reaction. The urethane prepared above is formulated with solvents to give a 40/50% solid content. One such suitable polyurethane resin is manufactured by the Spencer Kellogg Co. of Buffalo, New York under its designation M-SOCX and disclosed in their Bulletin TS-6193-R of 196 1. The asbestos floats (fibers) should be of a fine grade such as 7TF-1. It should be noted that where desired a small quantity (approximately 0.1 part by weight) of carbon black may be added to the mixture.

The coating ingredients are stored in a two part package. One part contains all the liquid ingredients, namely, the polyurethane prepolymer, amyl acetate and anhydrous xylene blended together, while the other part contains the dry ingredients, namely the natural emery grit, asbestos floats, magnesium silicate, and carbon black blended together. It is essential that the xylene and amyl acetate used be of a grade substantially free of water lest the resin polymerize prematurely on storage. Packaging in a one-part package has the disadvantage of requiring all the dry ingredients to be subjected to a dehydrating process, which would increase the cost of the coating system greatly. When readied for application, the dry ingredients are slowly stirred into the liquid and thoroughly mixed with a mechanical mixer to thoroughly wet all the dry ingredients. The mixture has a useful pot-life of up to 24 hours, as compared to a maximum of two hours for chemically every type. It has proven convenient to package the ingredients for approximately a five gallon quantity when mixed, or that amount can be readily applied even when the deck is hot (140 F.) and when spread over an area of approximately 30 square feet per gallon, which can be worked by one man after the mixture is deposited on the deck.

After the coating mixture is poured out of the container onto the deck, it flows readily and spreads rapidly to form a very shallow puddle. The coating can then be spread over the deck with a masonry trowel or with a long-handled paint roller to the desired coating thickness. When applied in the above manner, the emery particles are closely spaced, generally one particle deep, and the binder matrix between the particles has a thickness which is a minor fraction of the emery particle dimension. The binder matrix combines the proportion of excellent adhesion, toughness, impact resistance, flexibility, durability, good particle retentivity, and long wear resistance, while being easy to apply under the extremes of temperature encountered in the environmental conditions of an aircraft carrier flight deck, or hangar deck. In fact, it was found that the coating has exceptional and excellent adhesion to any moderately clean substrate to which it is applied. The coating applied to wood, metal (steel, aluminum, and stainless steel), old paint or old deck coating, dry, wet, or even submerged will set and adhere well. It has an application temperature tolerance that covers the entire range of normal seaport temperatures of F. to 140 F. Its application is unaffected by moisture and humidity and it can be applied successfully to a moist surface. Also it can be applied to contaminated oily or greasy surfaces with only a preparatory detergent washdown so that patching and repairs present no problem. The coating after mixing has a pot-life of atleast 8 hours as compared to a chemically curing system, which eliminates waste of material due to premature polymerization. The coating is weather resistant and is relatively unaffected by the fuel and lubricants that often are spilled on the deck. Standard pigments can be added to the mix for the color desired. Under moderate environmental conditions, the coating withstands foot traflic in 12 hours following application, light vehicular trafiic in 24 hours and full service in 48 hours.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

We claim: l

1. A high performance, non-slip coating for deck areas of ships, which coating comprises the following mixture of parts by weight:

Polyurethane resin 48 Amyl acetate 6 Xylene 6 Magnesium silicate 20 Fine asbestos fiber floats 10 Emery grit 12/30 sieve size and wherein the dry ingredients are continually added to the liquid component while mixing and then thoroughly mixed.

2. The coating according to claim 1 further including in said mixture 0.1 part by weight of carbon black.

References Cited UNITED STATES PATENTS 3,012,987 12/1961 Ansul 26031.2 N 3,252,775 5/1966 Tocci-Guilbert 51-298 3,450,653 6/1969 McClellan 26037 N 3,470,121 9/1969 Cobbledick 26037 N MORRIS LIEBMAN, Primary Examiner P. R. MICHL, Assistant Examiner US. 01. X.R.

26033.6 UB, 37 N 

